what possible reason would people have to do this?

Who isn't worried about gun-free national parks?

Thankfully the GOP is there to help bring weapons into the national parks, answering that worry that so many Americans talk about every day. "What do we possibly have to do to bring loaded weapons into Yellowstone National Park?" is dinner table conversation throughout the land. Sounds like a great idea for every family and surely nothing could ever go wrong, right? Besides, think of those doggone bison and gray wolf populations that were just starting to recover. Clearly we need to kill nature in order to save it.

(Americablog)